Midland Mainline (MML) was a British train operating company owned by the National Express Group and based in Derby. It was created after the privatisation of British Rail. Midland Mainline services operated from April 1996 to November 2007. Midland Mainline ran fast and semi-fast passenger services from London to the East Midlands and Yorkshire, on the Midland Main Line. Trains ran from London St Pancras which it used exclusively. Most services ran between London and either Sheffield, Derby, or Nottingham. Some services extended to Leeds, York, Barnsley and Burton upon Trent.